1. Buying back-links without verifying them

2. Posting duplicate content

3. Not putting many efforts in title tags

4. Not optimising or putting appropriate alt tags, Title Tags, Meta Tags etc on images

5. Using free hosting blogs

6. Keywords Stuffing

7. Writing thin content

8. Not formatting the content

9. Shifting your server may low down your ranking for the time being

10. Getting PBN links from non-related sites